Fluid operated clutch



Dec.' .10, 1946. H, VANDERZEE 2,412,436

FLUID OPERATED 'CLUTCH Filed March 22, 1944 2 Sheets-Sheet 1 Dec. 1.0, 1946. H. H. vANDr-:RZEE

FLUID OPERATED CLUTCH Fledjlarcn 22, 1944 2 Sheets-Sheet 2 ing links and levers. v are a uniform and continuous application of the Patented Dec. 10, 1946 FLUID OPERATED CLUTCH Harry H. Vanderzee, Racine, Wis., assignor to Twin Disc Clutch Company, Racine, Wis., a corporation of Wisconsin.

ApplicationMai-ch 22, 1944, Serial No. 527,620

6 Claims. (Cl. 192-85) My invention relates' to clutches and more particularly to those of the fluid actuated type in which any selected fluid under pressure, either gas or liquid, is applied to a piston which con stitutes the actuating element of the clutch.

Clutches of this general type wherein an annular piston applies the engaging pressure are well known and, for certain installations, they possess a, number o'f advantages overthe more commonclutch arrangement in which the engaging pressure is applied at spaced locations around the clutch through mechanisms includ- Some of these advantages engaging pressure around the clutch, quick action in engagement and disengagement which is particularly important when the associated ma chine is designed for repetitive, short Working cycles, and capacity for rapid acceleration and deceleration and quick reversals.

When employed under the foregoing conditions,v

the eiiicient control and dissipation of the genl erated heat presents a serious problem because it is important that the fluid cylinder assembly, including the release springs, be kept relatively cool. e

One object of my invention is to provide a uid operated clutch in which important manufacturing and operating advantages, relative toprioi" character indicated wherein the member which deiines a portion of they air cylinder also carries the release springs and transmits the reactive thrust of the fluid medium.

A further object is to provide a release spring mechanism for a clutch of the type wherein a pressure plate has toothed driving engagement with a hub or generally any rotating member, the mechanism being arranged to accommodate relative rotative movements of the plate due to worn teeth without hampering the effectiveness of the mechanism. l

These and further objects of my invention will be set forth in the following specification, reference being had to the accompanying drawings, and the novel means by which said objects are 2 eiiectuated will be definitely pointed out in the claims.

In the drawings: Fig. 1 is a longitudinal section of my improved clutch in disengaged position taken alongthe line I-l in Fig. 2.

Fig. 2 is an end view of the clutch looking vin the direction of the arrow 2 in Fig. 1. y

Fig. 3 is an enlarged, fragmentary, sectional view of the clutch as shown in Fig. l, but in engaged position.

Fig. 4 is an enlarged elevation of the head end of the spring bolt as Viewed in Fig. 1.

Fig. 5 is anenlarged, fragmentary view of the clutch engaging face of the pressure plate showing the relation of the head end of the spring bolt thereto.

Referring to thel drawings, the numeral l0 designates a shaft which for purpose of description will be regarded as 'the driven member and which is secured by a key il to a hub l2 having at one end a flange i3 which acts as the back or abutment plate of the clutch. The hub is peripherally splined or toothed at lli for axiallyslidable and rotarily driven engagement with internally toothed plates l5 that are alternately related to friction plates I6 which are externally toothed for engagement with` a driving member (not shown), such as ab' iiywheel or other part.

' ably mounted in the cylinder is a piston assern'n bly comprising a piston 2| provided with suitable packing 22 that may -be cup-shaped and an annular extension 23 that projects laterally from and is preferably integrally formed with a pressure plate 24 which, in the released position of the clutchshown in Fig. 1, abuts vthe inner end of the wall i9. The piston 2l abuts and is carried on the extension 23, cap screws 25 serving to rigidly secure these parts together, while the extension pilots the pressure plate 24 and the piston 2| in the cylinder 20, thus enabling the plate and piston to move freely without cocking and reducing wear of the packing 22. The radial portion of the packing is clamped between the pis-V ton 2l and extension 23.

The plate .24 is internally toothed forsdriving tion, such rotation would occur during engagement and disengagement of the clutch and would result in undue wear of the piston packing 2,2 with consequent leakage or blow by of the air. In a clutchwhose working cycle is repeated at short intervals. this wear becomes critical and lrequires frequent servicing of the unit. Further, where itis necessary 'that the clutch be quick acting, air leakage must be reduced to the utmost'minimum, otherwise the clutch will be characterized by slow action. f

Air, 4or any desired fluid, is introduced into the cylinder 20 through connecting'passages in the shaft I andhub I2. Specifically, a rotating air seal (not shown) is applied to either endrof the shaft I0, depending upon the position relation of thelloadtothe clutch, the right end being vs e' lected'in the present' instance. The vshaft IU-ex-v tends through the ring I1 andv would be supported normally in a Ibearing (not shown) before] receiving the seal which provides a connection between a, source of air under pressure and an tive to the ring I1, but the ability of the loolts 36- to move angularlyrelative to the plate maintains the full functional capacity of the release mechanism. Rotationbf each .spring bolt 36 about its axis is prevented by providing a lug 43 (see Fig. 5) which is oiiset from the head 35 that is preferably cylindrical in-shape and this lug loosely fits fa groove 44 formed in the Wall of the associated the atmosphere by means of continuous grooves 45 in and around this wall, the grooves being sufilciently deep to intersect the pockets 40. The grooves also assist in cooling the ring I1 and piston assembly by 'increasing the surface of the ring for radiation and the wiping action of the air as the clutch rotates. l

axial passage 26 which extends part way through the shaft I0.. Seals of this type are well known in the art. The inner end of the passage 2B communicates with radial 'passages 21 in the shaft. each of which is aligned with a radial passage 28 of larger diameter in the hub I2 and the outer end of each passage 28 is closed by a plug 29. Longi It wilibe observed that the piston assembly 1n the retracted position illustrated in Fig. 1 substantially fills the cylinder 20. Where air is emi v"position-be held to a minimum. The construcr tion shown accomplishes this result.

t'udinal passages 30 in the hub connect .the sevf eral passagesy 28 with/'radial recesses'3l in the ring I1,'the outer en of the recesses communicating with the cylinder 20. The difference in diameters of the passages 21 and 28 creates annular shoulders 32 constituting parts of the shaft vsurface and a seal ring 32a is compressed against each of the shoulders by a nut 33 threaded in the inner end of tle associated passage 28 to preventI air leakage along the shaft.

When air under pressure is supplied to the cyl-` inder 20the piston assembly, including the pressure plate 24, -is-'moved toward the left from the position shown in Fi'g. 1 to that indicated in Fig.

- 3, thus clamping the plates I5 and lli-against the 'f-iiange I3. The reactivlg thrust of the ring I1 is I8. Upon release 'of the plates are freed for retaken by the cap screw means of a spring actuated bolt arrangement which constitutes a feature of the invention. Ex-

' tending inwardly-from the clutch plate, contacting face of the pressure plate 24 is a, plurality of circumferentially, spaced sockets 34, each of which ,each shankv winch is included within 1the associatecl pocket, one end of the spring seating against the base o-f the pocket 'while the' opposite end abuts a sleeve nut 42 that is threaded on the shank and slidably fits the pocket wall. When the clutch is engaged, the springs are compressed.

The loose mounting of the bolts 36 in the pressure plate 24 and wall I9 enables these bolts to operate freely and without strain as the'teeth of thepressure plate Wear. This wear would permit small rotational movements of the plate 24 rela- The clutch is characterized, particularly in the air cylinder and operating mechanism portions thereof, by simplicity and compactness, ready ac-- cess for repair and replacement, and long life of the parts by reason of the cooling and piloting features.

I claim:

l .1. A fluid-operated clutch comprising in combination, a hub, friction members having toothed connection with the hub anda separate rotary part, respectively, a ring member Vabutting one end of the hub and forming therewith an annular cylinder for receiving the uid medium, an annular piston movable in the cylinder, a clutch pressure plate having toothed connection with the hub, the plate being piloted in the cylinder 'and movable in one direction by the piston, a plurality of bolts spaced around the plate, each having a head loosely fitting within a socket pro- Y direction.

2. A fluid operated clutch comprising in combination, a hub, friction members having toothed connection with the hub and a separate rotary part, respectively, a ring member abutting onej 'endof the hub andvforming therewith an an- .nular cylinder for receiving the fluid medium, an annular piston movable in the'cylinder, a

clutch pressure plate having toothed connection with the hub, the plate being piloted in the cylinder and movable in one direction by the piston, a plurality of bolts spaced around the plate, each having a head loosely tting within asocket provided in the plate and having a shank extending rotation of the bolt, and a helical spring encircling each shank between an' abutment thereon and the base of the associated pocket for shifting the plate in the opposite direction.

3. In clutch construction wherein a pressure plate has a toothed connection with `a rotary member and is shifted in one direction to engage the clutching members, means for shiftingthe plate in the opposite direction comprising a plurality of bolts spaced karound the plate each having a head loosely fitting within a socket provided in the plate and having a shank extending loosely through and into a correspondlngly positioned pocket in the member'whereby the bolts may move angularly relative to the plate, and a helical spring encircling each shank between an abutment thereon and the base of the associated pocket.

4. In clutch construction wherein a pressure plate has a toothed connection with a rotary member and is shifted in one direction to engage the clutching members, means for shifting the plate in the opposite direction comprising a plug 5. A uid operated clutch comprising a hub having an annular cylinder for receiving the fluid medium, an annular piston movable in the cylinder, a clutch pressure plate having toothed connection with the hub, the plate being movable in one direction by the piston, a plurality of bolts spaced around the plate, each having a head loosely tting within a socket provided in the plate andhaving a shank extending loosely through and into a correspondingly positioned pocket in themember, and a helical spring encircling each shank between an abutment thereon and the base of the associated pocket for shifting the platein the opposite direction.

6. A fluid operated clutch comprising a hub having an annular cylinder for -receivingthe fluid medium, an annular piston movable in the cylinder, a clutch pressure plate having toothed connection with the hub, the plate being movable in one direction by the piston, a plurality of bolts spaced around the plate, each having a head loosely fltting'within a socket provided in the plate and having a shank extending loosely through and into a correspondingly positioned pocket in the member., the head and socket wall having interengaging formations preventing rotation of the bolt, and a helical spring encircling each shank between an abutment thereon and the base of the associated pocket for shifting the plate in the opposite direction.

mnRY H. VANDERZEE. 

